Passing a do-not-call register into law would be the best option to protect Hongkongers’ personal data from telemarketing, the city’s privacy commissioner Stephen Wong Kai-yi said on Monday, a week before a public consultation on the issue was due to end.

“We would prefer setting up a do-not-call register through legislation, which would be better in terms of clarity and deterrence,” Wong said.

But he ruled out a blanket ban on all telephone promotions, saying it was not his decision to make.

Criminal sanctions for telemarketers not abiding by a do-not-call register are among three options on the table in a public consultation exercise currently under way. The others include enhancing trade-specific self-regulatory regimes and promoting the use of call-filtering applications on smartphones.

Wong’s office had been studying all three options, the commissioner said.

Since 2008, a register shielding those taking part from commercial electronic messages via fax, text message and pre-recorded calls has been operated free of charge by the Office of the Communications Authority. But it has been criticised by those who say it lets cold-callers run unrestrained.

Wong said the loophole for unsolicited calls came from an intention to leave space for start-ups to grow in the city, and the government did not want to discourage entrepreneurship with new laws.

“Some studies overseas show that [a statutory registry] actually benefits sales because businesses have a higher chance of success when their calls get through,” Wong said, adding that customers should be able to decide what calls they wanted to block.

The commissioner said fines for companies violating the Personal Data (Privacy) Ordinance were no comparison for those in the European Union, where penalties were calculated on the basis of business turnover. Similar heavy punishments would unlikely find their way through Hong Kong’s legislature, Wong said.